Patent · US Expired

Marking memory elements based upon usage of accessed information during speculative execution

US6721944B2 · kind B2 · utility

71Cited by
1References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 2001
Grant dateApr 13, 2004
Priority date
Expiry dateAug 22, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3842
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

One embodiment of the present invention provides a system that marks memory elements based upon how information retrieved from the memory elements affects speculative program execution. This system operates by allowing a programmer to examine source code that is to be compiled into executable code for a head thread that executes program instructions, and for a speculative thread that executes program instructions in advance of the head thread. During read operations to memory elements by the speculative thread, this executable code generally causes the speculative thread to update status information associated with the memory elements to indicate that the memory elements have been read by the speculative thread. Next, the system allows the programmer to identify a given read operation directed to a given memory element, wherein a given value retrieved from the given memory element during the given read operation does not affect subsequent execution of the speculative thread. The programmer is then allowed to insert a hint into the source code specifying that the speculative thread is not to update status information during the given read operation directed to the given memory eleme…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.